FluentDOM\Node\ChildNode\Implementation::before PHP Method

    public function before($nodes)
    {
        /** @var \DOMNode|Implementation $this */
        if ($this->parentNode instanceof \DOMElement && ($nodes = MutationMacro::expand($this->ownerDocument, $nodes))) {
            $this->parentNode->insertBefore($nodes, $this);
        }
    }